Continuation and completion of structure-activity studies on streptonigrin and lavendamycin, antitumor-antibiotics, and related, synthetic structures. Concurrent continuation of the investigation and implementation of inverse electron demand (4 + 2) cycloaddition reactions of heterocyclic azadienea: 1,2,4-triazines, 1,2,4,5-tetrazines, 1,2,3-triazines, 1,3,5-triazines and 1,2-diazines for the preparation of the agents under study. Total synthesis of prodigiosin (methylpentylprodigiosin) and related, naturally occurring pyrrolylypyrromethenes, tripyrrolic red pigments each possessing a common 2,2'-dipyrrole and each exhibiting significant antimicrobial and antifungal activity. Concurrent investigation of the utility of the inverse electron demand Diels-Alder reaction of 1,2,4,5-tetrazines as a viable approach to the preparation of polypyrroles. Total synthesis of tropolo-alkaloids: colchicine, a potent mitotic inhibitor, and the related structures, imerubrine and grandirubrine. The total synthesis of cyclopentenoid antitumor-antibiotics: sarkomycin, pentenomycins I - III, and dehydropentenomycin. Concurrent investigation of the inverse electron demand Diels-Alder reactions, (4 + 2) cycoloaddition, as well as the thermal (1 + 2), (3 + 2), and (3 + 4) cycloadditions of cyclopropenone ketals with electron deficient olefins and dienes. Total synthesis of deoxybouvardin and bouvardin (NSC 259968), naturally occurring and unusual cyclic hexapeptides possessing antitumor activity, and a series of related synthetic analogs. Evaluation of the antitumor properties of the series of agents prepared. Total synthesis of piperazinomycin, an antifungal antibiotic which possesses the nearly identical 14-membered paracyclophane skeleton which constitutes a partial structure of deoxybouvardin/bouvardin. Total synthesis of tylocrebrine, an antitumor-antibiotic, and concurrent investigation of the scope of the thermal generation and subsequent intramolecular Diels-Alder reactions of 2-trimethylsilyloxy-1-aza-1,3-butadines. Total synthesis of fredericamycin A (NSC 305263), an antitumor-antibiotic, and concurrent investigation of the cyclizaation reactions of areyl chromium carbene complexes. Evaluation of the antitumor properties of partial structures and synthetic agents related to fredericamycin A.